I
Immortal Sun
Guest
For most games, you could see HP as an abstract game element, if you wanted to; but you could also take it as just the way things worked, in that alternate reality. It's clearly not our world, because a real person can't reliably survive such hazards as a high-level character could, but exploring an alternate world has always been one of the big selling points for RPGs. (You could argue that minions are realistic, based on how things work in our own world, but they aren't consistent with how everything else works in their world.)
What 4E did was to take a hard stance, that HP were definitely just a game element that didn't signify anything deeper about how the world worked, and force everyone else to either take it or leave it. I don't think the designers necessarily realized how many people would see that as a deal-breaker.
I think if you're going to start suggesting that "in an alternate reality, things could be different" you have little ground to stand on in suggesting 4E's minion rules are flawed. In the 4E "alternate reality" that's clearly how things work.
By no means do you have to play in that specific alternate reality. But if we're going to rely on a "many worlds" theory and that in each of them "things may be different" then 4E is no better or worse than any other approach.
You're actually the first person I've seen complain about minion rules being immersion breaking, so perhaps the designers did account for that, and found the actual number of people who would see it as a deal-breaker not worth accounting for. They can't make everyone happy.